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/********************* */
/*! \file combination.cpp
** \verbatim
** Original author: taking
** Major contributors: none
** Minor contributors (to current version): none
** This file is part of the CVC4 prototype.
** Copyright (c) 2009, 2010, 2011 The Analysis of Computer Systems Group (ACSys)
** Courant Institute of Mathematical Sciences
** New York University
** See the file COPYING in the top-level source directory for licensing
** information.\endverbatim
**
** \brief A simple demonstration of the capabilities of CVC4
**
** A simple demonstration of how to use uninterpreted functions, combining this
** with arithmetic, and extracting a model at the end of a satisfiable query.
**/
#include <iostream>
//#include <cvc4/cvc4.h> // use this after CVC4 is properly installed
#include "smt/smt_engine.h"
using namespace std;
using namespace CVC4;
int main() {
ExprManager em;
SmtEngine smt(&em);
smt.setOption("tlimit", 100);
smt.setOption("produce-models", true); // Produce Models
smt.setOption("incremental", true); // Produce Models
smt.setOption("output-language", "smtlib"); // output-language
// Sorts
SortType u = em.mkSort("u");
Type integer = em.integerType();
Type boolean = em.booleanType();
Type uToInt = em.mkFunctionType(u, integer);
Type intPred = em.mkFunctionType(integer, boolean);
// Variables
Expr x = em.mkVar("x", u);
Expr y = em.mkVar("y", u);
//Functions
Expr f = em.mkVar("f", uToInt);
Expr p = em.mkVar("p", intPred);
// Constants
Expr zero = em.mkConst(Rational(0));
Expr one = em.mkConst(Rational(1));
// terms
Expr f_x = em.mkExpr(kind::APPLY_UF, f, x);
Expr f_y = em.mkExpr(kind::APPLY_UF, f, y);
Expr sum = em.mkExpr(kind::PLUS, f_x, f_y);
Expr p_0 = em.mkExpr(kind::APPLY_UF, p, zero);
Expr p_f_y = em.mkExpr(kind::APPLY_UF, p, f_y);
smt.assertFormula(em.mkExpr(kind::LEQ, zero, f_x)); // 0 <= f(x)
smt.assertFormula(em.mkExpr(kind::LEQ, zero, f_y)); // 0 <= f(y)
smt.assertFormula(em.mkExpr(kind::LEQ, sum, one)); // f(x) + f(y) <= 1
smt.assertFormula(p_0.notExpr()); // not p(0)
smt.assertFormula(p_f_y); // p(f(y))
cout << "Under the assumptions, prove x cannot equal y is valid: "
<< " CVC4 says " << smt.query(em.mkExpr(kind::DISTINCT, x, y)) << endl;
cout << "Now we call checksat on a trivial query to show that" << endl
<< "the assumptions are satisfiable: "
<< smt.checkSat(em.mkConst(true)) << "."<< endl;
cout << smt.getValue(x) << endl;
cout << smt.getValue(y) << endl;
cout << smt.getValue(f_x) << endl;
cout << smt.getValue(f_y) << endl;
cout << smt.getValue(p_f_y) << endl;
cout << smt.getValue(p_0) << endl;
cout << smt.getValue(f) << endl;
cout << smt.getValue(p) << endl;
return 0;
}
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